add nodeId proc to macros (#11456)

* add nodeId proc to macros

* add doc comment.

* fix typo

6 files changed, 18 insertions, 2 deletions

diff --git a/compiler/ast.nim b/compiler/ast.nim
index addb2c33b..c3ed33914 100644
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -666,7 +666,8 @@ type
     mInstantiationInfo, mGetTypeInfo,
     mNimvm, mIntDefine, mStrDefine, mBoolDefine, mRunnableExamples,
     mException, mBuiltinType, mSymOwner, mUncheckedArray, mGetImplTransf,
-    mSymIsInstantiationOf
+    mSymIsInstantiationOf, mNodeId
+
 
 # things that we can evaluate safely at compile time, even if not asked for it:
 const
diff --git a/compiler/condsyms.nim b/compiler/condsyms.nim
index 00ce352f2..3dc614a37 100644
--- a/compiler/condsyms.nim
+++ b/compiler/condsyms.nim
@@ -87,6 +87,7 @@ proc initDefines*(symbols: StringTableRef) =
   defineSymbol("nimHasDefault")
   defineSymbol("nimMacrosSizealignof")
   defineSymbol("nimNoZeroExtendMagic")
+  defineSymbol("nimMacrosGetNodeId")
   for f in low(Feature)..high(Feature):
     defineSymbol("nimHas" & $f)
 
diff --git a/compiler/vm.nim b/compiler/vm.nim
index 40d12db97..0496e37ca 100644
--- a/compiler/vm.nim
+++ b/compiler/vm.nim
@@ -1472,6 +1472,12 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
         regs[ra].node = copyNode(a)
       else:
         stackTrace(c, tos, pc, errFieldXNotFound & "ident")
+    of opcNodeId:
+      decodeB(rkInt)
+      when defined(useNodeIds):
+        regs[ra].intVal = regs[rb].node.id
+      else:
+        regs[ra].intVal = -1
     of opcNGetType:
       let rb = instr.regB
       let rc = instr.regC
diff --git a/compiler/vmdef.nim b/compiler/vmdef.nim
index 2f6cbcb85..54c18b03a 100644
--- a/compiler/vmdef.nim
+++ b/compiler/vmdef.nim
@@ -99,7 +99,7 @@ type
     opcNNewNimNode, opcNCopyNimNode, opcNCopyNimTree, opcNDel, opcGenSym,
 
     opcNccValue, opcNccInc, opcNcsAdd, opcNcsIncl, opcNcsLen, opcNcsAt,
-    opcNctPut, opcNctLen, opcNctGet, opcNctHasNext, opcNctNext,
+    opcNctPut, opcNctLen, opcNctGet, opcNctHasNext, opcNctNext, opcNodeId,
 
     opcSlurp,
     opcGorge,
diff --git a/compiler/vmgen.nim b/compiler/vmgen.nim
index 0b41fed28..898916c64 100644
--- a/compiler/vmgen.nim
+++ b/compiler/vmgen.nim
@@ -1324,6 +1324,8 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest; m: TMagic) =
     c.gABx(n, opcNodeToReg, a, a)
     c.genAsgnPatch(arg, a)
     c.freeTemp(a)
+  of mNodeId:
+    c.genUnaryABC(n, dest, opcNodeId)
   else:
     # mGCref, mGCunref,
     globalError(c.config, n.info, "cannot generate code for: " & $m)
diff --git a/lib/core/macros.nim b/lib/core/macros.nim
index b0414153e..73f5790fa 100644
--- a/lib/core/macros.nim
+++ b/lib/core/macros.nim
@@ -1426,6 +1426,12 @@ proc boolVal*(n: NimNode): bool {.compileTime, noSideEffect.} =
   if n.kind == nnkIntLit: n.intVal != 0
   else: n == bindSym"true" # hacky solution for now
 
+when defined(nimMacrosGetNodeId):
+  proc nodeID*(n: NimNode): int {.magic: NodeId.}
+    ## Returns the id of ``n``, when the compiler has been compiled
+    ## with the flag ``-d:useNodeids``, otherwise returns ``-1``. This
+    ## proc is for the purpose to debug the compiler only.
+
 macro expandMacros*(body: typed): untyped =
   ## Expands one level of macro - useful for debugging.
   ## Can be used to inspect what happens when a macro call is expanded,